Routing policies#

Routing policies determine how Route 53 responds to queries. The following table highlights the key function of each type of routing policy:

Policy What it Does
Simple Simple DNS response providing the IP address associated with a name
Failover If the primary is down (based on health checks), routes to secondary destination
Geolocation Uses the geographic location you’re in (e.g., Europe) to route you to the closest region
Geo-proximity Routes you to the closest region within a geographic area
Latency Directs you based on the lowest latency route to resources
Multivalue answer Returns several IP addresses and functions as a basic load balancer
Weighted Uses the relative weights assigned to resources to determine which one to route to

Simple routing policy#

  • An A record is associated with one or more IP addresses.
  • It uses round-robin.
  • It does not support health checks.

The following diagram depicts an Amazon Route 53 Simple routing policy configuration:

Simple routing policy configuration

Failover routing policy#

  • Failover to a secondary IP address
  • Associated with a health check
  • Used for active-passive
  • Routes only when the resource is healthy.
  • Can be used with ELB
  • When used with Alias records, set Evaluate Target Health to “Yes” and do not use health checks.

The following diagram depicts an Amazon Route 53 Failover routing policy configuration:

Failover routing policy configuration

Geo-location routing policy#

  • The geolocation routing policy caters to different users in different countries and different languages.
  • It contains users within a particular geography and offers them a customized version of the workload based on their specific needs.
  • Geolocation can be used for localizing content and presenting some or all of your website in your users’ language.
  • It can also protect distribution rights.
  • It can be used for spreading the load evenly between regions.
  • If you have multiple records for overlapping regions, Route 53 will route to the smallest geographic region.
  • You can create a default record for IP addresses that do not map to a geographic location.

The following diagram depicts an Amazon Route 53 Geolocation routing policy configuration:

Geolocation routing policy configuration

Geo-proximity routing policy#

  • Requires Route Flow
  • Used for routing traffic based on the location of resources and, optionally, shift traffic from resources in one location to resources in another

Latency based routing policy#

  • AWS maintains a database of latency from different parts of the world.
  • It is focused on improving performance by routing to the region with the lowest latency.
  • You create latency records for your resources in multiple EC2 locations.

The following diagram depicts an Amazon Route 53 Latency based routing policy configuration:

New York
[Not supported by viewer]
Sydney
[Not supported by viewer]
Singapore
[Not supported by viewer]
Latency based routing policy configuration

Multi-value answer routing policy#

  • Used for responding to DNS queries with up to eight healthy records selected at random

The following diagram depicts an Amazon Route 53 Multivalue routing policy configuration:

Multi-value routing policy configuration

Weighted routing policy#

  • The weighted routing policy is similar to simple with the exception that you can specify a weight per IP address.

  • You create records that have the same name and type, and assign each record a relative weight.

  • You can define numerical value that favors one IP over another.

  • To stop sending traffic to a resource, you can change the weight of the record to 0.

The following diagram depicts an Amazon Route 53 Weighted routing policy configuration:

Weighted routing policy configuration

DNS Records with Route 53

Route 53 Traffic Flow, Resolver, and Charges